The overall concern for the quality of the environment has raised renewed interest in the manner in which various chemicals are synthesized, refined, stored, and used. Specifically, there is a growing concern regarding the manufacture, storage and use of fossil fuels, principally hydrocarbon fuels at the refinery, during wholesale storage and distribution, as well as during retail storage and sale.
For example, hydrocarbon fuels such as gasoline and household fuel oil are often stored in tanks which are buried at central distribution points or at retail service stations. During storage, transport and sale of these materials tank leaking or spilling often occurs, creating an area of environmental contamination which may ultimately prove hazardous.
One common means of alleviating the environmental hazard is removing and disposing of this contaminated soil in a landfill. However, landfill disposal of this contaminated matter may often be a time consuming and expensive endeavor as well as being subject to burdensome government regulations.
Contaminated soil may also be treated to remove the hydrocarbon waste through various means. Processes for the thermal remediation of contaminated soil have been developed and refined. For example, Clarke, U.S. Pat. No. 4,420,901 discloses a tractor drawn farm implement for decontaminating fields. Goedhart, U.S. Pat. No. 4,648,332 discloses a fluidized bed furnace for decontaminating soil. Przewalski, U.S. Pat. No. 4,700,638 discloses an apparatus for the disposal of hazardous material such as dioxin and polychlorinated biphenols through a thermal process. Keating II et al,
U.S. Pat. No. 4,815,398 discloses a rotary dryer for thermally decontaminating soils. Gerken et al, U.S. Pat. No. 4,782,625 discloses a materials dryer used to decontaminate soils. Finally, Hardison et al, U.S. Pat. No. 4,667,609 discloses an infrared apparatus for thermally decontaminating soils. Other methods of treatment include processing soil in converted stationary asphalt plants. However, these processes are not portable and generally produce a high concentration of particulate exhaust.
However, the apparatus and methods disclosed in these patents generally utilize expensive and sophisticated machinery to dispose of contaminants such as dioxin and polychlorinated biphenols. Moreover, these mechanisms use high volumes of air, which necessitates a variety of complex exhaust filtering and cleaning systems. Finally, the previously disclosed devices and processes generally are either completely stationary or, alternatively, are portable but require the expenditure of extended time, energy, and space in transport and set up.
Accordingly, there is a need for a portable thermal remediation apparatus which is capable of removing contaminants from soil and other particulate compositions which does not require complex exhaust treatment systems, and which may be used at the contamination site with a minimum expenditure of space, set-up time, and energy.